


Infinite Experimentation

by tepalixed



Series: Infinite Engineering [2]
Category: Infinity Train (Cartoon)
Genre: Amelia and One-One Are Frenemies, Canon-Compliant, Exploiting Fictional Physics, Fix-It, Gen, Post-Season 2, Tulip Can Actually Ask Questions Now That She's Friends With Two Reality-Bending Train Experts, Tulip Learns To Code, Unfortunately Atticus Is Not In This Fic Because He Canonically Died A Lame Death Offscreen
Language: English
Status: In-Progress
Published: 2020-02-18
Updated: 2021-02-16
Packaged: 2021-02-27 20:55:34
Rating: General Audiences
Warnings: No Archive Warnings Apply
Chapters: 3
Words: 3,918
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/22792105
Author URL: https://archiveofourown.org/users/tepalixed/pseuds/tepalixed
Summary: Tulip, Amelia, and One-One try to abuse the train's powers to cure world hunger. It's harder than they thought.
Relationships: Amelia (Infinity Train)/Biscuits, Tulip (Infinity Train)/Onions
Series: Infinite Engineering [2]
Series URL: https://archiveofourown.org/series/1637590
Comments: 18
Kudos: 46





	1. Proof of Concept

**Author's Note:**

> This story is a sequel to [Infinite Potential](https://archiveofourown.org/works/20319595). If you haven't read that first, go read it!

**Summary for the Chapter:**

> Amelia learns something very interesting.

Amelia did not cackle in triumph, thank you very much. It was more of a tight-lipped ha-HA, accompanied by furrowing her eyebrows and stretching the mouth into a slight smile. Whenever she thought she'd figured out something new about this blasted train's code, it always felt good - but she'd learned to never let her guard down until after the test. Just because this kid had brought her another goal to work towards, just because she had begun to piece together the idea that she could feel something like hope again, wasn't enough to make her drop her guard. Definitely not a cackle. 

Then she took another look at the wrapped lump in front of her and emitted a dangerously cheery "Heh".

Amelia leaned back from her keyboard, at her desk in the engine, and cradled her head in her hands. "I can't believe that worked. That's what you needed, Train? That?"

Amelia took two hands and unwrapped the package. Inside sat the prized contents - a multicolored mess of mush blanketed in a sea of red, smushed between two golden-brown orbs, one of which glowed in places with a green light. It was the best burger Amelia had seen in the last thirty years.

"It actually worked. I got the train to accept a gosh-darned burger as a passenger."

A smile split across Amelia's face as she examined the greasy contents. Almost stamped across one side, a green eight flickered faintly. Leave it to the train to make even the easiest way to hack together contact with the outside world as thoroughly dumb as possible.

But the proof of concept wouldn't test itself. Slowly, Amelia took a bite out of the side. Slowly, she let the flavor settle onto her tongue. Thirty years later, fast-food burgers still tasted like trash. Tears streamed down her eyes.

Slowly, a pitter-patter of feet grew louder in the direction of the entrance to the engine. "Hello, Miss Amelia!" an obnoxiously familiar voice proclaimed. "You seem like you're suffering." 

Amelia wiped her face with the sleeve of her burger-holding arm. "I'm not suffering."

"Oh. Well, uh, good to know. Keep up the not suffering." One-One's robotic eyes narrowed. "Are you holding something?" he asked, scurrying in for a closer look. "Ah. A wrapper. I love those things," he said, eye displays flickering in happiness. "Looks like it even comes with a free burger!"

An opportunity to score some easy goodwill with the most powerful being on the train? Amelia would be a fool to not take it. "You can have the wrapper if you want," she said, gesturing with her currently full hand.

"Thanks! Throwing away wrappers is always fun." chirped One-One. Little legs flailing for balance, he climbed up Amelia's chair and onto her shoulder. Upon feeling his weight Amelia's hand instinctively jerked towards her emergency taser before remembering that now that they were technically "friends", it wasn't needed. Terrifying little thing. She didn't really know why One kept walking on those tiny stubs; now that One had its powers back, wouldn't manipulating gravity be simpler?

"Ah," he said. "is that a zero?"

"What," said Amelia, turning to face the little robot. He looked ahead and downwards.

"Hmm, that was rather fast..." said Sad-One, "but a zero does mean you're free to go!"

"What?" said Amelia, turning to follow his gaze, with equal parts horror and bewilderment. 

"Wait just one second; I'll get you right where you belong!"

"What," said Amelia, and that's when she realized One-One was looking straight at what she held in her hand. Or more specifically, what was left of it. Her burger now had a bite-sized chunk missing - and with a start she realized that that missing chunk had been taken directly out of the center of the eight. And an eight without a center looked just like...

Suddenly, a few paces away, a beam of light shot out from thin air and traced the outline of a door, quickly solidifying into solid colors. With a clunk, the newly-formed door twisted outwards to reveal a multicolored tunnel of light, and at the end, some sort of unfamiliar black plastic that was still immediately recognizable as a rubbish bin.

Amelia's jaw dropped. Her mind whirled. Her stomach rumbled. This... this was impossible, wasn't it? She looked down at her arm, just to check - yup, her own number was still there and still huge. What was going on??

Suddenly, One-One took a flying leap off her shoulder, snatching her treasured prize out of her hand on the way down. Amelia stood up with a start, but it was too late - he landed with a clank on the floor, scuttled over to the edge of the portal, picked up the now thoroughly unpalatable soggy blob of food, and tossed it through. He turned to her still-shocked face. "There you go! I threw it out for you!" 

Amelia stared at the door. No - she glared at the door. Salvation from train food had just slipped through her fingers. "Did you just steal my burger?!"

One-One's entire body moved in a nod. "Yup! Get it? Because the place where a wrapper belongs..." - he shifted his front two legs into the air- "...is a garbage bin!"

Amelia sputtered in outrage. Months of reverse engineering, thrown down the drain.

One-One paused with his hands in midair. "Did you not think it was funny?"

Amelia glared. "No."

"Oh. I'm sorry. I thought you seemed sad, and could use a little joke."

"What I could use is a burger. That burger."

One-One fell back down to the floor with a clank and walked to stand in front of Amelia. "Sorry." he said, then paused for a second. "Here; I know just how to make it up to you."

There was a pause. Then, with a brilliant high-pitched noise, a second beam of light shot out through the air and formed a second door, right next to the first one. It began to emit a yellow light, which suddenly materialized into a white package. It fell onto the floor with a "plorp", and after a second both doors faded out of existence. "Presenting, an apology burger," said Sad-One.

Amelia stared at what indeed looked like another perfectly-wrapped package. According to the logo, it was even from the same chain as its slain comrade. Her anger began to drain away.

Then a thought struck her. The gears in Amelia's mind whirred. "Where did you get that from?"

"Some place in Hibernia, I think? Hmm, I haven't checked its name in a while..." mused One-One.

"You got that from Earth?"

"Oh! Yes. Definitely your world." nodded Glad-One.

"I spent months hacking together a crazy workaround to get something here from Earth, and you could have just opened a portal there this entire time?!" 

"Mm-hmm" nodded One-One. "If you wanted one, you should have asked!"

It took all of Amelia's willpower not to punch that dumb ball in the eye projectors right then and there. Refusing to use all-powerful power was exactly why she had killed him before. She was awfully close to doing it again.

Amelia took a deep breath. "I have been trying to make decent biscuits on this train for the last ten years. Are you saying I could have just waltzed off the train and bought one?"

"Oh, goodness, no. Passengers can't leave until their number is zero," One-One explained. "And your wrapper wasn't a passenger!" he brought one leg up to his chin in thought. "Although, I think it did have an entry in the arrivals log. Don't know why it's missing from all of the other databases. Huh. A mystery for the ages."

"Huh. I wonder why," said Amelia with what was hopefully a level voice. Darn - so there were more databases.

"Hmm..." said One-One, "Well, I trust you, miss Amelia." He began to walk off towards his port at the front of the engine. "If you need to get more outside stuff", he yelled over his shoulder (not that he had shoulders), "let me know and we can try to convince Mum together!". 

"Thank you," waved Amelia, as he left. Mum, of course, was the train itself. Stupid sentient robots. She walked over and picked the white package off the floor, unwrapping it to reveal the burger underneath. Still warm.

Her mouth began to frown a bit less. So that test wasn't a waste after all. And, she'd learned something valuable: things from the outside world could enter the train. Systems, after all, were never 100% hackproof. Were she a cackling person, she might have begun rubbing her hands together in glee. As it was, she furrowed her eyebrows and stretched her mouth into a slight smile.

**Notes for the Chapter:**

> Now that Season 2 confirmed that things can leave the train, "Tulip saves the world" could actually be canon! Unlike the writers, who are afraid of silly things like "ruining all the drama by answering questions about their mysterious setting" and "making sure Earthly society doesn't become fundamentally unrecognizeable", I'm not a coward. It's time for Tulip to do what she does best: use her brain.
> 
> Amelia is such a criminally underused character for how amazing she is. I hope I did her justice.


	2. Brainstorming

Tulip stumbled down the slope into the engine room and yawned, still a bit groggy from the sedatives. "Hi! I’m back, and I brought the blueprints!” she called out.

Amelia, who had been typing away at rows of computer monitors, whirled around in surprise. “Who’s there?!” she yelled, grabbing the taser from under her desk and whipping it around to point at Tulip. Tulip flinched, one arm instinctively jerking towards her back to grab a pipe which wasn’t there. Amelia relaxed. “Oh, it’s you.” 

Tulip let herself relax too. “Sorry. Too loud?”

“No,” lied Amelia. “You surprised me, that’s all.”

Tulip rubbed her neck. “Sorry!”

"Hi, Miss Tulip!" came a second reply from the front of the engine. “What’s that you’re holding?”

Tulip took a moment to wipe her eyes. “It’s a new power supply box! This time, I hope it’ll work with my phone charger.”

“It feels like your home has a lot of defective boxes in it.” commented One-One.

“I also brought a few new spools of wire, a replacement screwdriver for the one that broke, and I got you a present, Amelia! A teakettle! ‘Cause, you know, you’ve said you liked tea, right?”

“I’m a bit miffed you think I haven’t figured out how to brew hot tea here already.”

“Well, I was looking for a kettle here before, and I didn’t see any-”

Without looking away from her monitor, Amelia grabbed the orb gun from its hook on the wall with one hand, and with her other hand, pulled open a drawer and grabbed a well-worn orb inside it. In one fluid motion, she fit the orb into the circular slot on the orb gun, pointed the gun at an empty mug on her desk, and fired. In a burst of light, the mug was now filled with steaming liquid. She took a sip.

Tulip stood in awe. “You have a tea orb?”

“Made it myself,” smirked Amelia, taking a sip. “I started with an orb for this horrible earl gray from a café car, and messed around with a copy until somehow I turned it into this lovely breakfast tea.” Amelia took another sip and softly smiled. “A few years back I revisited the code and added some milk, and I’ve enjoyed this blend ever since.”

With a clatter, Amelia hung the org gun back up on the wall. Tulip stood still for a moment. “Wow. That’s really cool.”

“Thank you.” She took another sip. “So what were you on about?”

“Curing world hunger!”

“Ooh, a noble sentiment. Let’s see your ideas!” said One-One. Tulip unwrapped a set of blueprints from her backpack and spread them across a desk.

Amelia peered at the blueprint’s title. “An… onion 3D printer?”

“Yeah!”

She frowned. “Is this blueprint meant to be some sort of machine, or a fantastical idea you’d find in a train car?”

One-One jumped up onto the bench to peer at the blueprints. “I don’t think an idea would look this blue and papery.” Amelia shot him a glare, and then shot him another one for not turning around to look at the first one. 

“No, like, a 3D printer which prints onions!”

“A 3D printer? What, does it print origami?”

“Printing origami?” mused One-One. “I think we already used that for a train car. Feels a bit derivative.”

“No,” exclaimed Tulip. “Like, the things that print plastic?”

“Plastic?” asked Amelia. “How would the ink stick to the plastic?”

Tulip paused. “Have you never heard of a 3D printer?”

“No?”

“Oh,” said Tulip. “Right. You’ve been on the train for years, so you probably don’t know about all the stuff that’s been invented since then.”

Amelia crossed her arms. “Yes, yes, I’m old. We know that already. Are you going to tell me what a 3D printer is?”

Tulip gestured to the paper. “Here’s my idea for a design. There’s a printing head, which moves around on these two axes at right angles. Then there’s a third axis going up and down, and it moves along these four pillars at the corners. So by moving the motors in the right amounts, we can move the printing head wherever we want.”

“And what’s so special about the printing head?”

Tulip cleared her throat. “That’s where the plastic comes from. It’s super hot. Then it sticks to the other pieces of plastic, and the printing head moves along wherever it needs to in 3D to put down a layer of plastic. Then it puts down layers and layers and layers until finally you build up your 3D thing to print.”

Tulip cleared her throat. “And, I want to do that with onions, instead of plastic, so we’d need some kind of onion filament which we could make infinite onions with.”

“What is it with you and onions?” asked Amelia.

“Hey, they’re delicious!” interjected Tulip. “But I know that not everyone likes onions, so I added this,” she said, gesturing to a flat rectangle on the bottom part of the machine. “This is a keyboard, so if people don’t want onions, they can type in a different food.”

“A different food.” asked Amelia, dryly.

“Yeah. You know, if you want pizza or something.”

Amelia grimaced. “This won’t work,” she sighed, and turned away to walk back to her computer. Tulip stood there for a second in shock. 

“Hey!” yelled Tulip, hands on her hips. “That’s all you have to say? You can’t just do that!”

“And you can’t just magic up something which will fix all your problems without properly planning it out first.” drawled Amelia, “Let me know when you’ve put a bit more thought into it.”

“Ugh!” Tulip threw her hands in the air, grabbed the blueprint off the desk, and stomped towards Amelia. “You said you’d help me! You said you’d finally had the chance to do something good for once!”

“Ending hunger is a good goal, Tulip, but it’s more complicated than one machine can handle.”

Tulip walked towards Amelia and jumped in between her and her desk. “That’s not the point!” Tulip yelled, exasperated. “If you’re so sure it won’t work, can you at least tell me why so I can improve it?”

“Not if you’re setting yourself impossible goals!”

“You were the conductor! Of an infinite train! You can’t just say that something’s impossible and run away!”

“You’re right! I was the conductor,” thundered Amelia, whipping an arm out to point at the broken remains of the robot suit she'd tried to kill Tulip with, stacked in a messy pile of cracked pieces. “And look at how well that turned out for me, huh?”

There was silence in the engine room. Tulip stepped back. One-One’s feet pitter-pattered towards the two of them.

Amelia sighed. Tulip scratched her neck. Eventually, after a long while, Amelia plopped wearily into her chair.

“When I first took control of the train, everything seemed easy. I thought the train could solve all my problems.”

She shook her head and looked up. “But it’s never as simple as it seems. You change one line of code and discover twenty more that depended on it, and then when you fix those you find out the errors were actually how the system passed messages between programs and everything is flaming wreckage and you don’t have a backup because this is a train and there’s no backups on a train.” Amelia took a sip of tea from the mug on her desk. “Programming lesson number one: it’s the details that get you. It’s all the little details. So when you’re designing something, make sure to specify as much detail as you can, and no more than you need to.”

Tulip, nodded, determined, while Amelia continued. “Think about the details of your daft little keypad for a second. Allowing people to type in any food they want is a bloody stupid idea. Your machine would need to know the names of every single food in the world.” she took another sip, then paused mid-sip, looking down at her mug. “Across every culture, too. If I asked your machine for iced tea but it gave me your garish American monstrosity, I’d clobber it with my bare hands.”

“Oh.” said Tulip. “That’s actually a really good point. And different foods are made of different things, too, so the printer would need to print all of them.”

“Not to mention,” One-One chimed in, “what buttons would you put on the keyboard? And in what alphabet? I wouldn’t even be able to reach the higher buttons, and Mum only speaks zeroes, ones, and infinities. You’d have to teach your machine about every single alphabet and every single food in that alphabet, and that would take a lot of time and textbooks.”

“Are the buttons pressure sensitive? Do they need to be cleaned? What part of your machine detects when they’re pressed? Don’t waste time thinking about these problems if you have to. It’s hard enough trying to force the train to do the impossible,” said Amelia, smiling wearily. “So only work on impossible problems if you have to.”

Tulip frowned. “Those are all really good questions. I guess I’ll scrap the keyboard and a few other parts. Thanks, guys.”

Amelia sighed, stood up, and walked over to Tulip. Carefully, she lowered one hand onto Tulip’s shoulder. 

“There, there.” 

Tulip looked up, quizzically. “What?”

“I’m rubbish at this sort of thing. Did that help?”

“Not really.”

“Well then.” said Amelia. There was a pause. “I’ll see what I can do. At least I can help you avoid the same mistakes that I did.” 

Tulip smiled. “Want to head back to the drawing board?”

Amelia’s mouth twitched upwards. “Sure.”


	3. Market Research

**Summary for the Chapter:**

> Tulip finally starts learning to hack the train.

Sure, the train was full of magical nonsense, but in retrospect, it was really Tulip's fault for not assuming it's nonsense all the way down.

She had been waiting for this moment for a long time. It had taken a lot of pestering, some passionate arguing, and some promises Tulip probably couldn't keep, but in the end Amelia had given in. The cool grump in question sat sideways on her chair, facing her monitor, while Tulip sat eagerly on a box nearby. One-One climbed up onto the desk, knocking over some papers, and gingerly scooted around the scalding mug of tea. It was finally time for Tulip to learn how the train’s code worked.

“So the first thing to know about the train is that at its core, everything boils down to two numbers.”

Tulip smiled. She’d heard a bit about this before, and she was excited to finally hear the details. “Zero and one?”

“No. Nan, and infinity.”

Tulip frowned.

“What? No zero?”

“Nope.”

“Where are all the other numbers?”

“Perished in an analytic toaster accident fifty years ago,” answered One-One. “Don’t worry! I rebuilt them out of Nan and infinity.”

Amelia bit her lip, frowned, and turned to One-One. “Was that, by any chance, a red big square thing, lots of spirals on top, gray side melted through?”

“Melted? Sounds like it fought to the bitter end.” said One-One.

“I wouldn’t know. Chucked it into a lava car with a bunch of other rubbish. I always wondered what that thing was.”

One-One held up an arm. “Unfortunately there’s a lot of lava cars. Was it the watery lava car? The minecart lava car? The knock your socks off car? The disintegration ray car?”

“Look, I don’t know the ID. It was a long time ago.”

Tulip frowned. “Wait, wait, hold on. What’s Nan?”

Amelia huffed slightly. “Not a Number. It’s not important.”

“Not a number?”

“Yes, and it’s one of the two numbers the train is built out of.”

“Hold on, I thought you said it wasn’t a number?”

“Nan is a number.”

“Not a number is a number?”

Amelia stared at the child in front of her as though she had asked the most obvious question in the world. Which she had. “Yes.”

Tulip’s brow furrowed. Amelia tilted her head in thought. “Technically it’s two numbers, but you can’t tell them apart anyways.”

Tulip let out a frustrated groan.

“Also, the train will interpret anything which isn’t infinity as Nan. Learned that the hard way when I was poking around with the wires behind that wall. Bloody thing read each molecule in my arm as a nan and crashed half my programs. Ruined a perfectly good sewing machine, too. I think it was still trapped in the code there last time I checked. ”

Tulip drew in a breath, then released it. “...okay then. So. Nan and infinity. Are we talking about the same infinity? The, like, biggest number?”

“Yes, yes, a number bigger than any other number,” began Amelia. Tulip nodded. Of course an infinite train would run on infinity; that just made sense.

“...except for Nan.” added Amelia.

Tulip’s brain screeched to a halt.

“Nan is bigger than infinity?”

“Unfortunately, nope.” said One-One. “Nan could never dream of being bigger than anything.”

Tulip pointed an accusatory finger outwards. “Didn’t you just say infinity was bigger than nan?”

“No, infinity isn’t bigger than nan.” added One-One. “Where did you get that idea?”

“What?” said Tulip. “Didn’t you just say-” she paused. “Which is bigger? Infinity or Nan?”

“Infinity,” commented One-One. 

“But only if you ask in that order.” added Amelia.

“So Infinity is bigger than Nan, then.” 

“No.”

Tulip’s brow furrowed. “OK, I should probably ask. Infinity isn’t, like, equal to Nan, right?”

“Nope.” said One-One. “Never compare yourself to Nan. It’s always wrong.”

“What?” said Tulip, slightly louder.

Amelia rolled her eyes. “Nan is never bigger than anything. It’s also never smaller than anything or equal to anything. Maximum of infinity and Nan is infinity, though, because infinity came first.”

“Doesn’t maximum mean bigger than the other one?”

“Not if you’re Nan. Nan is special.”

“Ugh.” Tulip threw up her hands. “Computers are dumb.”

Amelia shot her a merciless smile. “And we haven’t even gotten to negative infinity yet.” She took her arms off the keyboard and gave them a stretch. “All the rest of the numbers are made out of nan and infinity. I’m pretty sure everything in the train boils down to nan and infinity in some way or another,” said Amelia, leaning back into her chair. “It’s bothersome because if you’re programming a mind and accidentally divide something by zero it’ll blow up to infinity and roast any other numbers near it.” She turned to stare at Tulip, eyes haunted by knowledge not meant for mortal eyes. “And roasted numbers are easier for messages to digest, so the servers do it on purpose to pop fresh kernels off the stacks and into the popcorn heaps during the update steps.”

“Fresh kernels?”

One-One hopped up onto the table, then turned to stare directly into Tulip’s eyes. “Never install outdated kernels.”

**Notes for the Chapter:**

> Someone made a computer which runs on Nan and infinity in [real life](https://www.youtube.com/watch?v=5TFDG-y-EHs) and now i refuse to believe the train runs any other way
> 
> (By the way every single piece of fictional nightmare math Amelia mentions in this chapter? That's how computers work in real life. The device you're reading this with does math that way.)


End file.
